As is well known in the art, scleral depressors are used to facilitate examination of the fundus or interior surface of the eye including the retina. During such an examination, and particularly during the study of areas of the retina, it is sometimes necessary to control the position of the eye.
During vitrectomy surgery, instruments are placed through the sclera or white wall of the eye, into the vitreous cavity to repair or correct problems inside the eye. Complete surgical dissection of the peripheral vitreous and retina is not possible without deliberate depression of the sclera. Under most situations, the surgeon's hands are occupied with the surgical instruments. Accordingly, an assistant is required to perform “scleral depression.” Several sclera depressors have been designed for this purpose.
Substantially all known prior art sclera depressors include a handle and a blade or depressing element that is attached to the handle and which extends therefrom. The blade is arranged to be either straight or at an offset angle from the handle to facilitate manipulation of the blade.
One known example of such a scleral depressor is available from Inami Ophthalmic Instruments under the name Morizane. The blade of the Morizane scleral depressor is in the form of a relatively flat triangle that faces in the same direction as the direction of the axis of the elongated handle. The depressor is designed to allegedly control the rotation of the eyeball along with the depression of the same.
Scleral depressors used during surgery typically have a blade depressing element in the form of a cylinder or that has a bulbous structure. The classical and optimal means to provide depression during surgery involves inserting the scleral depressor parallel to the axis of the eye and depressing the sclera in toward the center of the eye, perpendicular to the wall of the eye.
Typically, the patient is lying in a supine position with the surgeon at the top of the head and the assistant at the side, oriented 90° from the surgeon. The face and body of the patient are covered by sterile cloths with the operative eye being the only exposed body part.
Using the current straight scleral depressors that are available, the assistant, who is typically on the temporal or lateral side of the eye, has several obstacles to adequate scleral depression. For example, depression on the nasal side of the eye is difficult to access as it's on the opposite side as the assistant. His or her hand has to reach all the way around the eye to access this region. The superior side of eye is also difficult to access due to the assistant's hand interfering with the surgeon's hands and instruments and the inferior side of the eye is slightly limited to depression by the cheekbone. Even further, the handle and shaft of the depressor frequently hit the optical system for viewing inside the eye which are either hanging from the microscope above the eye (with the lowermost portion a few millimeters above the eye) or are sitting on the surface of the eye.
There is, therefore, a need for a scleral depressor that allows an assistant to apply a depression force to the sclera at almost any location and in almost any direction without interfering with the surgeon or any of the surgical instruments.